*{margin:0;padding: 0;box-sizing: border-box;}
button{border:0px;}
ul{list-style: none;}
a{text-decoration: none;}
.d-inline{display: inline;}
.d-inline-block{display: inline-block;}
.d-block{display: block;}
.p-re{position: relative;}
.p-ab{position: absolute;}
.f-l{float: left;}
.f-r{float: right;}
.border{border:1px solid black;}
.w-990{width:990px;}
.mg-auto{margin:0 auto;}